1. Field of the Disclosure
A technique disclosed in this specification relates to a switching circuit and a power conversion circuit. In detail, a technique disclosed in this specification relates to a switching circuit including a charge pump unit and a power conversion circuit.
2. Description of Related Art
A voltage-driven switching element, such as an IGBT or a MOSFET, is used for various purposes, and for example, is used for a power conversion circuit, such as a converter device which transforms a DC voltage or an inverter device which converts a DC voltage to an AC voltage. In order to drive the voltage-driven switching element, a switching element which operates based on a control signal is used. The switching circuit is configured to connect a gate of the voltage-driven switching element to a positive electrode of a DC power supply in a turn-on period and to connect the gate of the voltage-driven switching element to a negative electrode of the DC power supply in a turn-off period. With this, the voltage-driven switching element is turned on with an increase in gate voltage in the turn-on period and is turned off with a decrease in gate voltage in the turn-off period. In this kind of switching circuit, a charge pump unit configured to generate a negative voltage may be provided. For example, Japanese Patent Application Publication No. 2012-249492 (JP 2012-249492 A) discloses a switching circuit including a charge pump unit configured to generate a negative voltage based on a pulse signal.